Abstract

A plethora of materials is available to the modern day house designer but selecting theappropriate material is a complex task. It requires synthesising a multitude ofperformance criteria such as initial cost, maintenance cost, thermal performance andsustainability among others. This research aims to develop a Knowledge-basedDecision support System for Material Selection (KDSMS) that facilitates the selectionof optimal material for different sub elements of a roof design. The proposed systemalso has a facility for estimating roof cost based on the identified criteria. This paperpresents the data modelling conceptual framework for the proposed system. The roofsub elements are modelled on the Building Cost Information Service (BCIS) StandardForm of Cost Analysis. This model consists of a knowledge base and a database tostore different types of roofing materials with their corresponding performancecharacteristics and rankings. The system’s knowledge is elicited from an extensivereview of literature and the use of a domain expert forum. The proposed systememploys the multi criteria decision method of TOPSIS (Technique of rankingPreferences by Similarity to the Ideal Solution), to resolve the materials selection andoptimisation problem. The KDSMS is currently being developed for the housingsector of Northern Ireland.Keywords: TOPSIS, cost modelling, knowledge-based system, decision supportsystem, roofing material selection.